The present invention generally relates to media products for receiving printed images thereon. More particularly, the invention described herein involves image-receiving sheet materials each having at least one ink-receiving layer with a specialized and distinctive chemical composition therein that is used to provide a number of important benefits in a simultaneous fashion. These benefits include but are not limited to a high degree of compatibility between the ink materials being delivered and the ink-receiving layer under consideration, rapid drying times, the generation of smear-fast printed images, the control of ink-coalescence (defined below), the attainment of uniform gloss levels (and a high level of gloss if desired), as well as numerous other benefits relating to image quality.
Substantial developments have been made in the field of electronic printing technology. A wide variety of highly-efficient printing systems currently exist which are capable of dispensing ink in a rapid and accurate manner. Thermal inkjet systems are especially important in this regard. Printing units using thermal inkjet technology basically involve an apparatus which includes at least one ink reservoir chamber in fluid communication with a substrate (preferably made of silicon [Si] and/or other comparable materials) having a plurality of thin-film heating resistors thereon. The substrate and resistors are maintained within a structure that is conventionally characterized as a xe2x80x9cprintheadxe2x80x9d. Selective activation of the resistors causes thermal excitation of the ink materials stored inside the reservoir chamber and expulsion thereof from the printhead. Representative thermal inkjet systems are discussed in, for example, U.S. Pat. No. 4,771,295 to Baker et al. and U.S. Pat. No. 5,278,584 to Keefe et al. which are both incorporated herein by reference.
The ink delivery systems described above (and comparable printing units using thermal inkjet technology) typically include an ink containment unit (e.g. a housing, vessel, or tank) having a self-contained supply of ink therein in order to form an ink cartridge. In a standard ink cartridge, the ink containment unit is directly attached to the remaining components of the cartridge to produce an integral and unitary structure wherein the ink supply is considered to be xe2x80x9con-boardxe2x80x9d as shown in, for example, U.S. Pat. No. 4,771,295 to Baker et al. However, in other cases, the ink containment unit will be provided at a remote location within the printer, with the ink containment unit being operatively connected to and in fluid communication with the printhead using one or more ink transfer conduits. These particular systems are conventionally known as xe2x80x9coff-axisxe2x80x9d printing units. A representative, non-limiting off-axis ink delivery system is discussed in, for example, U.S. Pat. No. 5,975,686 to Hauck et al. which is also incorporated herein by reference. The present invention as described below (which involves a plurality of novel ink-receiving print media products) is applicable to both on-board and off-axis systems (as well as any other types which include at least one ink containment vessel that is either directly or remotely in fluid communication with a printhead containing one or more ink-ejecting resistors therein). Furthermore, while the print media materials outlined herein will be discussed with primary reference to thermal inkjet technology, it shall be understood that they may be employed in connection with other ink delivery systems and methods including but not limited to piezoelectric drop devices of the variety disclosed in U.S. Pat. No. 4,329,698 to Smith and dot matrix units of the type described in U.S. Pat. No. 4,749,291 to Kobayashi et al., as well as other comparable and diverse systems designed to deliver ink using one or more ink delivery components/assemblies. In this regard, the claimed print media products and methods shall not be considered xe2x80x9cprint method-specificxe2x80x9d.
In order to effectively generate printed images using the various ink transfer techniques and systems discussed herein (again, with primary but not exclusive reference to thermal inkjet technology), ink-receiving print media materials must be employed which are capable of efficiently accomplishing this goal. Ideally, to achieve maximum efficiency, print media materials should be able to provide numerous advantages and benefits including but not limited to (1) a high level of light-fastness, with the term xe2x80x9clight-fastnessxe2x80x9d being generally defined herein to involve the capacity of a print media product to retain images thereon in a stable fashion without substantial fading, blurring, distortion, and the like over time in the presence of natural or made-made light; (2) rapid drying times in order to avoid smudging and image deterioration immediately after printing is completed due to contact with physical objects and the like; (3) the fast and complete absorption of ink materials in a manner which avoids image distortion caused by color bleed (e.g. the undesired migration of multi-colored ink components into each other) and related difficulties; (4) a highly water-fast character (with the term xe2x80x9cwater-fastxe2x80x9d being generally defined to involve the ability of a print media product to produce a stable image with little or no fading, run-off, distortion, and the like when the image is placed in contact with moisture); (5) the generation of xe2x80x9ccrispxe2x80x9d images with a distinct and defined character; (6) the ability to produce printed products which are substantially xe2x80x9csmear-fastxe2x80x9d, with this term being generally defined to comprise the production of images that will not exhibit smearing, blurring, and the like when rubbed or otherwise physically engaged with a variety of objects ranging from the components of the printing apparatus being employed to the print operator""s hands, fingers, and the like; (7) the control of an undesired condition known as xe2x80x9cink-coalescencexe2x80x9d which is defined herein to involve a phenomenon wherein wet ink droplets applied to an inkjet printing medium fail to spread sufficiently to eliminate the unprinted space between the droplets, thereby causing significant image deterioration problems; (8) the capacity to generate printed images with desired levels of gloss wherein the final product is characterized by uniform gloss levels throughout the entire image in order to achieve a professional and aesthetically-pleasing printed media sheet; (9) low material costs which enable the print media products of interest to be employed for mass market home and business use; (10) chemical compatibility with a wide variety of ink formulations which leads to greater overall versatility; (11) excellent levels of image stability and retention over long time periods; (12) minimal complexity from a production and material-content standpoint which leads to reduced fabrication costs and greater product reliability; and (13) a high level of gloss-control which is achievable in a rapid and effective manner during production through only minor adjustments in the manufacturing process. The term xe2x80x9cgloss-controlxe2x80x9d is generally defined herein to involve the ability, during fabrication, to generate a print media product having high-gloss levels for the production of photographic quality images if desired, a semi-gloss character if needed, or other gloss parameters. In particular, the manufacturing process should be highly controllable in order to achieve a variety of different gloss characteristics without requiring major adjustments in processing steps and materials.
In the past, many different print media sheets using a wide variety of ingredients, production techniques, layering arrangements, and the like have been fabricated for a multitude of specific purposes. For example, as generally discussed in the representative patent documents listed below, the following items have been investigated and/or employed in the production of print media products to achieve a broad spectrum of goals: modifications in the types of materials being used, the amounts of such materials, the relative particle sizes thereof, the particular layering arrangements being chosen, and the adjustment of various factors including pore size, pore volume, layer thickness, particle orientation, surface roughness, surface rigidity, air permeability, and other similar parameters. Representative patents (incorporated herein by reference) which discuss at least one or more of the above-listed factors (and others) are as follows: U.S. Pat. Nos. 4,391,850; 4,440,827; 4,446,174; 4,474,847; 4,567,096; 4,623,557; 4,642,247; 4,780,356; 4,785,313; 4,879,166; 5,008,231; 5,013,603; 5,091,359; 5,104,730; 5,194,347; 5,266,383; 5,354,634; 5,397,619; 5,463,178; 5,472,773; 5,514,636; 5,576,088; 5,605,750; 5,609,964; 5,635,297; 5,691,046; 5,723,211; 5,753,588; 5,755,929; 5,804,293; 5,863,648; 5,882,388; 5,912,071; 5,928,789; 5,962,124; 5,965,244; 5,977,019; 5,985,076; and 6,063,489.
Notwithstanding the various media products discussed in the above-listed patents and prior activities in this field, a need remains for print media materials (namely, ink-receiving sheets) which are able to capture and retain clear, distinct, and accurate images thereon that are likewise characterized by a number of specific benefits in combination. These benefits include but are not limited to items [1]-[13] recited above both on an individual and simultaneous basis in a substantially automatic manner (with the simultaneous achievement of such goals being of particular importance and novelty). The attainment of these objectives is especially important regarding the following specific items: gloss-control (with high gloss levels and gloss-uniformity being of primary interest in a preferred embodiment), excellent light-fastness, rapid drying time, an effective level of ink-coalescence control, and the generation of clear, durable, smear-fast, and distinct printed images. The present invention and its various embodiments perform all of the functions recited above in a uniquely effective and simultaneous manner while using a minimal number of material layers, chemical compositions, and production steps. In particular (as will become readily apparent from the discussion provided herein), the foregoing advantages and attributes are achieved through the employment of at least one ink-receiving layer having a very special ingredient therein, the use of which in a print media product is entirely novel and offers the above-listed benefits. As a result, print media structures of minimal complexity are created that nonetheless exhibit a substantial number of beneficial characteristics and features in an unexpectedly efficient fashion. In this regard, the present invention represents a distinctive and important advance in the print media and image generation fields. Specific information concerning the novel print media materials of the invention and specialized fabrication methods associated therewith (which are equally unique) will be presented below in the following Summary of the Invention, Brief Description of the Drawings, and Detailed Description of Preferred Embodiments Sections.
It is an object of the present invention to provide highly efficient print media products for receiving inks, pigments, toners, and other colorants thereon so that a printed image may be generated.
It is another object of the invention to provide highly efficient print media products which enable the generation of stable printed images thereon from a variety of different coloring agents in many divergent forms.
It is another object of the invention to provide highly efficient print media products which facilitate the generation of printed images that are light-fast and water-fast as defined above.
It is another object of the invention to provide highly efficient print media products wherein the printed images produced thereon may be generated using a wide variety of printing technologies including but not limited to those which employ thermal inkjet technology.
It is another object of the invention to provide highly efficient print media products which are able to retain printed images thereon that exhibit an excellent degree of stability (including the avoidance of color bleed, namely, the undesired blending of colorants into each other) over prolonged time periods and under conditions of varying temperature, humidity, and the like.
It is another object of the invention to provide highly efficient print media products wherein the printed images produced thereon are characterized by rapid drying times.
It is another object of the invention to provide highly efficient print media products wherein the printed images thereon are substantially smear-fast when placed in contact with physical objects under a wide variety of environmental conditions.
It is another object of the invention to provide highly efficient print media products which avoid problems associated with ink-coalescence so that clear and distinct printed images can be generated.
It is another object of the invention to provide highly efficient print media products which have the capacity to generate printed images with desired levels of gloss (preferably high) wherein the final printed image is characterized by uniform gloss levels throughout the entire image plane in order to achieve a professional and aesthetically-pleasing printed media sheet.
It is another object of the invention to provide highly efficient print media products wherein the overall level of gloss is readily controlled without major adjustments to the production process, with such process allowing the fabrication of high-gloss or semi-gloss products in an effective and economical manner.
It is another object of the invention to provide highly efficient print media products which are able to effectively accomplish all of the above-listed goals and others (including the generation of images that are substantially water-fast and highly-defined) in a simultaneous fashion, with this aspect of the invention being accomplished in accordance with the unique layering arrangements and chosen construction materials discussed herein.
It is a further object of the invention to provide highly efficient print media products which are able to effectively accomplish all of the above-listed goals using a minimal number of material layers and construction materials.
It is an even further object of the invention to provide highly efficient print media products which employ layering arrangements and construction materials that are readily suited to large scale mass-production fabrication processes in an economical fashion.
It is an even further object of the invention to provide highly efficient print media products that are readily used in a wide variety of different printing systems with differing colorants (e.g. inks, pigments, toners, and the like) for many diverse purposes.
It is a still further object of the invention to provide highly efficient, rapid, and economical manufacturing methods which may be employed to produce the print media products of the present invention as discussed herein.
Novel and effective print media products (also characterized herein as xe2x80x9cprint media sheetsxe2x80x9d, xe2x80x9cink-receiving sheetsxe2x80x9d, and the like) are described below which offer numerous advantages and benefits over prior structures. These benefits and advantages include, without limitation, the simultaneous achievement of items [1]-[13] recited above with particular reference to (A) gloss-control (wherein high gloss levels and gloss-uniformity are of primary interest in a preferred embodiment); (B) excellent light-fastness; (C) rapid drying time; (D) a high degree of ink-coalescence control; and (E) the generation of clear, durable, smear-fast, and distinct printed images. In this regard, the claimed invention represents a significant advance in the print media technology and image generation fields.
As a preliminary point of information, the present invention shall not be restricted to any particular component types, sizes, material-selections, arrangements of print media materials, chemical compositions, layering sequences, numbers of layers, layer orientations, thickness values, porosity parameters, and other related factors unless otherwise stated herein. For example, it shall be understood that one or a plurality of novel ink-receiving layers containing the desired and special ingredient discussed herein may be employed in connection with the claimed media sheets. In this regard, the current invention shall not be restricted to any number of layers containing the chosen ingredient formulations provided that at least one of such layers is used. Likewise, the location of the ink-receiving layer(s) on or within the media sheet may be varied as desired and employed in combination with one or more other material layers located above or below the claimed layer(s) of interest. It shall therefore be emphasized that this invention shall cover the ink-receiving layer or layers of interest (e.g. those that employ the special ingredient specified herein) regardless of where such layer(s) are located provided that they are able to receive on or within at least part of the ink compositions being delivered by the chosen printing system. Accordingly, this invention shall be construed in its broadest sense to cover a print media product (and method for producing the same) which employs at least one ink-receiving layer having the chosen special ingredient therein [namely, a poly(vinyl alcohol-ethylene oxide) copolymer] so that this layer can receive at least part of the ink materials being delivered. In this manner, a printed image can be generated having the desired characteristics listed above.
Furthermore, the numerical values recited in this section and the other sections set forth below constitute preferred embodiments designed to provide optimum results and shall not limit the invention in any respect. In particular, it shall be understood that the specific embodiments discussed herein and illustrated in FIGS. 1-4 (along with the particular construction materials associated therewith) constitute special versions of the invention which, while non-limiting in nature, can offer excellent results and are highly distinctive. All recitations of chemical formulae and structures set forth in the following discussion are intended to generally indicate the types of materials which may be used in this invention. The listing of specific chemical compositions which fall within the general formulae and classifications presented below are offered for example purposes only and shall be considered non-limiting unless explicitly stated otherwise.
The claimed invention and its novel developments are applicable to a wide variety of printing systems with particular reference to those that employ thermal inkjet technology as previously discussed. Likewise, a number of different ink materials can be used in connection with the invention without limitation, with the term xe2x80x9cink materialsxe2x80x9d being defined to encompass compositions incorporating dyes, pigments, liquid or solid toners, and other colorants without restriction. Furthermore, such materials (e.g. colorants) shall encompass both chromatic (e.g. colored) and achromatic materials (black/white) without restriction. In this regard, the claimed print media products shall not be considered xe2x80x9cink-specificxe2x80x9d or xe2x80x9cprinting method-specificxe2x80x9d in any fashion.
It should also be understood that the present invention shall not be limited to any particular construction techniques (including any given material deposition procedures, layering arrangements, and the like) unless otherwise stated below. For example, the terms xe2x80x9cformingxe2x80x9d, xe2x80x9capplyingxe2x80x9d, xe2x80x9cdeliveringxe2x80x9d, xe2x80x9cplacingxe2x80x9d, xe2x80x9cpositioningxe2x80x9d, xe2x80x9coperatively attachingxe2x80x9d, xe2x80x9coperatively connectingxe2x80x9d, xe2x80x9cconvertingxe2x80x9d, xe2x80x9cprovidingxe2x80x9d, xe2x80x9clayeringxe2x80x9d, and the like as used throughout this discussion and as claimed shall broadly encompass any appropriate manufacturing procedures including, without limitation, roll-coating, spray-coating, immersion-coating, cast-coating, slot-die coating, curtain coating, rod-coating, blade-coating, roller application, and other related production methods. In this regard, the invention shall not be considered xe2x80x9cproduction method-specificxe2x80x9d unless otherwise stated herein, with the recitation of any particular fabrication techniques, layer deposition methods, number of layers applied in a given step, and the like being set forth for example purposes only.
Likewise, it shall be understood that the terms xe2x80x9coperative connectionxe2x80x9d, xe2x80x9coperative attachmentxe2x80x9d, xe2x80x9cin operative connectionxe2x80x9d, xe2x80x9cin operative attachmentxe2x80x9d, xe2x80x9coperatively attachedxe2x80x9d, xe2x80x9cpositioned onxe2x80x9d, xe2x80x9clocated onxe2x80x9d, xe2x80x9cpositioned abovexe2x80x9d, xe2x80x9clayered onxe2x80x9d, xe2x80x9cpositioned over and abovexe2x80x9d, xe2x80x9clocated over and abovexe2x80x9d, xe2x80x9capplied over and abovexe2x80x9d, and the like as used and claimed herein shall be broadly construed to encompass a variety of divergent layering arrangements and assembly techniques. These arrangements and techniques include but are not limited to (1) the direct attachment of one material layer to another material layer with no intervening material layers therebetween; and (2) the attachment of one material layer to another material layer with one or more material layers therebetween provided that the one layer being xe2x80x9cattached toxe2x80x9d, xe2x80x9cconnected toxe2x80x9d, or xe2x80x9cpositioned over and abovexe2x80x9d the other layer is somehow xe2x80x9csupportedxe2x80x9d by the other layer (notwithstanding the presence of one or more additional material layers therebetween). Use of the phrase xe2x80x9cdirect attachmentxe2x80x9d, xe2x80x9cdirectly attached onxe2x80x9d, xe2x80x9cdirectly attached toxe2x80x9d, xe2x80x9cdirectly positioned onxe2x80x9d, xe2x80x9cdirectly located onxe2x80x9d, and the like shall signify a situation wherein a given material layer is secured to another material layer without any intervening material layers therebetween. Any statement used herein which indicates that one layer of material is xe2x80x9cabovexe2x80x9d, xe2x80x9coverxe2x80x9d, xe2x80x9cpositioned over and abovexe2x80x9d, or xe2x80x9con top ofxe2x80x9d another layer shall involve a situation wherein the particular layer that is xe2x80x9cabovexe2x80x9d, xe2x80x9coverxe2x80x9d, xe2x80x9cpositioned over and abovexe2x80x9d or xe2x80x9con top ofxe2x80x9d of the other layer in question shall be the outermost of the two layers relative to the external environment. The opposite situation will be applicable regarding use of the terms xe2x80x9cbelowxe2x80x9d, xe2x80x9cunderxe2x80x9d, xe2x80x9cbeneathxe2x80x9d, xe2x80x9con the bottom ofxe2x80x9d, and the like. The characterizations recited above (with particular reference to xe2x80x9cpositioned over and abovexe2x80x9d) shall be effective regardless of the orientation of the print media materials under consideration and, for example, shall encompass a situation where the ink-receiving layer may be placed on either side of the substrate in question. Again, in the current invention, the claimed ink-receiving layer or layers may be located at any position within the print media sheet provided that at least some of the ink materials being delivered by the chosen printing system are able to come in contact with such layer or layers, followed by the receipt of ink materials therein and/or thereon. Thus, while the drawing figures associated with this invention (and the preferred embodiments discussed below) shall illustrate the claimed ink-receiving layer(s) on top of the media sheet as the uppermost/outermost structures which are exposed to the external environment with no other layers thereon, the claimed invention shall not be restricted to this design which is offered for example purposes only. As a final note, the terms xe2x80x9ctopxe2x80x9d, xe2x80x9cuppermostxe2x80x9d, and xe2x80x9coutermostxe2x80x9d as applied to a given layer in the claimed structure shall again be construed to involve that layer which is at the top of the print media product in question with no other layers thereon and is exposed to the external environment. When such layer faces the ink delivery components of the printer unit, it is typically the first component of the media product to receive incoming ink materials with no other layers thereon.
Furthermore, any and all recitations of structures, layers, materials, and components in the singular throughout the claims, Summary of the Invention, and Detailed Description of Preferred Embodiments sections shall also be construed to encompass a plurality of such items unless otherwise specifically noted herein.
As previously indicated, highly effective and versatile print media materials designed to receive ink materials thereon for the generation of clear, stable, and distinct printed images are provided. These media materials are again characterized by excellent gloss levels, a high degree of gloss-uniformity, and a desirable degree of ink-coalescence control as defined above. Many different ink delivery systems can be employed to generate the printed images of interest on the claimed media products without limitation although the use of devices that incorporate thermal inkjet technology are again preferred. Regardless of which ink delivery system is chosen, the present invention is capable of offering the considerable benefits listed above which include more efficient, rapid, and reliable image generation.
The following discussion shall constitute a brief and general overview of the invention which shall not limit the invention in any respect. More specific details concerning particular embodiments and other important features of the invention will again be recited in the Detailed Description of Preferred Embodiments section set forth below. All scientific terms used throughout this discussion shall be construed in accordance with the traditional meanings attributed thereto by individuals skilled in the art to which this invention pertains unless a special definition is provided herein.
As previously stated, the claimed invention involves one or more novel print media products (discussed in connection with a plurality of preferred embodiments) which are characterized by improved functional abilities, namely, more efficient image generation (e.g. excellent gloss-control/gloss-uniformity, rapid drying, image clarity, the ability to control ink coalescence, light-fastness, water-fastness, smear-fastness, color-bleed avoidance, and the like which are all achieved in a simultaneous and automatic fashion). The components and novel features associated with the claimed print media products will now be briefly summarized.
In order to produce a preferred print media product in accordance with the invention, a support structure, xe2x80x9csupportxe2x80x9d, or xe2x80x9csubstratexe2x80x9d (with all of such terms being considered equivalent from a structural and functional standpoint) is initially provided on which the other layer or layers associated with the print media product reside. Many different construction materials can be employed in connection with the substrate including those which are made from paper, plastics, metals, or composites of such materials without limitation although paper (any commercially-available type) is preferred. More detailed data regarding substrate construction materials will be presented below. The chosen substrate may be coated or uncoated on either or both sides thereof. In a preferred embodiment designed to provide optimum results, the substrate will include an upper surface (also characterized herein as a xe2x80x9cfirst sidexe2x80x9d) and a lower surface (also characterized herein as a xe2x80x9csecond sidexe2x80x9d), with at least one of such surfaces/sides (preferably the upper surface or both surfaces) being covered with a substantially non-porous, non-absorbent, and ink-impermeable composition in the form of a coating layer. A representative and exemplary coating composition associated with this embodiment involves polyethylene when a paper substrate is employed. However, other coating/substrate combinations can be used without limitation, or the application of substrate coatings can be eliminated entirely if desired as determined by routine preliminary pilot testing.
Positioned (e.g. provided) over and above the substrate (and secured thereto with xe2x80x9cdirect attachmentxe2x80x9d being preferred but not necessarily required) is at least one xe2x80x9cink-receiving layerxe2x80x9d. From a functional standpoint, the ink-receiving layer is designed to provide a high degree of xe2x80x9ccapacityxe2x80x9d (e.g. ink-retention capability) in connection with the media product, to facilitate rapid drying of the printed, image-containing media product, to create a media product with a smooth/even surface, to ensure that the desired gloss characteristics are maintained in the finished product, and to generate a stable printed image with desirable degrees of ink-coalescence control and the like. To accomplish these goals, the ink-receiving layer is comprised of a special material which has numerous functions including but not limited to binding capabilities, ink-absorptivity, the capacity to affix and retain printed images in a highly stable manner, and the like. This special material involves at least one poly(vinyl alcohol-ethylene oxide) copolymer. The term xe2x80x9ccopolymerxe2x80x9d basically and generally relates to a polymer which contains two or more different monomers. The poly(vinyl alcohol-ethylene oxide) copolymer to be employed in the claimed ink-receiving layer has the following basic chemical/polymeric structure:
xe2x80x83"Parenopenst"CH2CHOH"Parenclosest"x"Parenopenst"OCH2CH2"Parenclosest"y
[wherein x=about 1000-8000, and y=about 10-500]
It should be noted and understood that the above-listed xe2x80x9cxxe2x80x9d and xe2x80x9cyxe2x80x9d values are presented for example purposes only and constitute representative/preferred embodiments in a non-limiting fashion Such numbers may be subject to change if needed and desired in accordance with routine preliminary testing. Further and more detailed information concerning the above-listed composition (and at least one or more commercial sources for this material) will be provided below in the Detailed Description of Preferred Embodiments section.
If a substrate is employed which is coated (e.g. polyethylene-coated paper in a preferred embodiment), the ink-receiving layer(s) of this invention which incorporate at least one poly(vinyl alcohol-ethylene oxide) copolymer (along with any layers thereover or thereunder) are optimally (but not necessarily) placed on the side or sides that are covered with the chosen coating formulation (e.g. polyethylene and the like).
The ink-receiving layer of interest which is designed to provide the important benefits listed above may involve many different variants without limitation provided that: (1) at least one ink-receiving layer is employed, with this layer being composed entirely or partially of one or more poly(vinyl alcohol-ethylene oxide) copolymers; and (2) the ink-receiving layer is located on or within the claimed print media product so that it receives at least some of the ink materials thereon or therein which are delivered to the media product by the chosen printer unit. Accordingly, it is a novel and functionally important feature of this invention to provide a print media product which includes, at the very least, a substrate and at least one ink-receiving layer that is entirely or partially produced from at least one poly(vinyl alcohol-ethylene oxide) copolymer either in the layer or on top of it with both variants being encompassed within the invention. Nonetheless, at this time, preferred embodiments of the invention will now be summarized.
A first embodiment will encompass a print media product which includes the substrate listed with above with at least one ink-receiving layer positioned over and above or otherwise operatively attached to the substrate which comprises at least one poly(vinyl alcohol-ethylene oxide) copolymer. This composition again offers numerous important functions ranging from that of a binder to a drying time improvement additive without limitation. While the claimed invention shall not be restricted to any particular numerical quantities or amounts in connection with the poly(vinyl alcohol-ethylene oxide) copolymer, an exemplary and preferred embodiment designed to offer optimum results will involve the preparation of an ink-receiving layer that includes not less than about 70% by weight of the desired poly(vinyl alcohol-ethylene oxide) copolymer (about 80-90% by weight=optimum). The foregoing percentage values shall represent the total amount of poly(vinyl alcohol-ethylene oxide) copolymer being used whether a single composition is employed or multiple poly(vinyl alcohol-ethylene oxide) copolymers are used in combination. It should be noted that, unless otherwise stated herein, all percentage figures describing the material content of the various layers discussed in the claims, Summary of the Invention, and Detailed Description of Preferred Embodiments sections shall involve xe2x80x9cdry weightxe2x80x9d, namely, the weight of the chosen component in the dried material layer of interest.
In the current embodiment, the ink-receiving layer discussed above may further comprise one or more additional ingredients therein combined with the claimed copolymer. For example, at least one pigment of a particulate or non-particulate character (organic or inorganic) may be employed within the ink-receiving layer. If this material is used, the ink-receiving layer will optimally include about 15-30% by weight pigment therein. Again, the foregoing percentage values (and all other numerical quantities expressed herein unless otherwise noted) shall involve the total amount of pigment in question whether a single pigment or multiple pigments in combination are employed. Further information and more specific data involving representative pigment compositions and combinations thereof will be set forth in the Detailed Description of Preferred Embodiments section. While the claimed invention shall not be restricted to the employment of any particular pigment materials or mixtures thereof, exemplary and preferred (non-limiting) pigments suitable for use in the ink-receiving layer or layers of this invention will involve the following compositions without limitation: silica (in precipitated, colloidal, gel, sol, or fumed form), cationic-modified silica (e.g. alumina-treated silica in an exemplary and non-limiting embodiment), cationic polymeric binder-treated silica, aluminum oxide, magnesium oxide, magnesium carbonate, calcium carbonate, pseudo-boehmite, barium sulfate, clay, titanium dioxide, gypsum, and mixtures thereof). It should also be understood that, while preferred in the current embodiment, the use of a pigment composition or compositions in the ink-receiving layer shall be considered optional in nature.
With continued reference to the non-limiting embodiment that is currently being discussed, while the claimed poly(vinyl alcohol-ethylene oxide) copolymer summarized herein exhibits a binder function along with other special capabilities, at least one or more additional binder materials (characterized herein as xe2x80x9csupplemental binder compositionsxe2x80x9d) can also be optionally included in the ink-receiving layer(s). The term xe2x80x9csupplemental binder compositionxe2x80x9d shall be employed herein to involve binder materials other than the claimed poly(vinyl alcohol-ethylene oxide) copolymer. Likewise, the current embodiment shall not be limited to any particular types, quantities, or number of supplemental binder compositions. In a preferred and non-limiting version of the present embodiment, the ink-receiving layer will include about 10-30% by weight supplemental binder composition therein. Again, the foregoing percentage values (and all other numerical quantities expressed herein unless otherwise noted) shall involve the total amount of supplemental binder compositions(s) in question whether a single supplemental binder or multiple supplemental binders in combination are employed. Further information and more specific data pertaining to representative supplemental binder compositions and combinations thereof will be provided in the Detailed Description of Preferred Embodiments section. While the claimed invention shall not be restricted to the use of any particular supplemental binder compositions and mixtures thereof, exemplary and preferred examples of these materials include, without limitation, the following: polyvinyl alcohol and derivatives thereof, starch, SBR latex, gelatin, alginates, carboxycellulose materials, polyacrylic acid and derivatives thereof, polyvinyl pyrrolidone, casein, polyethylene glycol, polyurethanes (for example, a modified polyurethane resin dispersion), polyamide resins (for instance, an epichlorohydrin-containing polyamide), mixtures thereof, and others without restriction. It should also be understood that the use of supplemental binder compositions in the ink-receiving layer shall be considered optional in nature. Likewise, if multiple supplemental binder compositions are to be employed (e.g. at least two or more), a still further version of the present embodiment will involve a situation in which all of the supplemental binders being used are different from each other. For example, a mixture of (1) an epichlorohydrin-containing polyamide; and (2) a modified polyurethane resin dispersion combined with the chosen poly(vinyl alcohol-ethylene oxide) copolymer can provide favorable results. Again, the present invention shall not be restricted to this particular variant of the claimed print media sheet which is being summarized for example purposes only.
In summary and as outlined in considerable detail herein, the claimed ink-receiving layer shall encompass the use of at least one or more poly(vinyl alcohol-ethylene oxide) copolymers alone or with one or more additional ingredients. The present invention shall not be restricted to any particular additional ingredients or amounts thereof, with the following representative and non-limiting additional ingredients being employable if desired: (1) at least one pigment (without any supplemental binder compositions); (2) at least one supplemental binder composition (without any pigments); or (3) at least one pigment and at least one supplemental binder composition in combination. It should also be noted that any or all of the foregoing variants may incorporate one or more subsidiary additives ranging from surfactants to lubricant compositions and preservatives (discussed further below) if needed and desired as determined by routine preliminary testing. Likewise, the claimed invention shall not be restricted to any particular number of ink-receiving layers which contain the desired poly(vinyl alcohol-ethylene oxide) copolymer(s) which may range from one to multiple layers directly adjacent to each other or separated by one or more other material layers. As previously stated, it is preferred that the top/uppermost/outermost layer in the media products of the present invention involve the claimed ink-receiving layer which contains at least one poly(vinyl alcohol-ethylene oxide) copolymer. However, it is also contemplated that the ink-receiving layer or layers comprised of the claimed copolymer may be located anywhere on or within the print media products as needed and desired as along as such layer(s) can, in some fashion, receive all or part of the ink materials being delivered by the printer unit. All of these variations are again applicable to each of the other embodiments discussed herein as well as those which are covered by the claims set forth below.
Another embodiment is likewise of particular interest in this case, the selection of which will be based on routine preliminary pilot testing taking into account, for example, the type of ink to be used in connection with the print media products and other factors. All of the information, variants, potential layering arrangements, parameters, terms, definitions, and other items listed above relative to the first embodiment shall be applicable to and incorporated by reference in the alternative embodiment which will now be discussed. The key difference between the above-listed first embodiment and the embodiment to be summarized below involves the content of the ink-receiving layer. Basically, in the current embodiment of the claimed print media product, a substrate is again provided of substantially the same type as listed above. With reference to the ink-receiving layer, this structure is again positioned (e.g. provided) over and above the substrate or otherwise operatively attached thereto with xe2x80x9cdirect attachmentxe2x80x9d of this structure as defined herein being preferred but not necessarily required.
The ink-receiving layer in this embodiment is particularly unusual in that it preferably involves a structure consisting essentially of at least one poly(vinyl alcohol-ethylene oxide) copolymer as previously defined in connection with the first embodiment. Thus, all of the information presented above regarding the poly(vinyl alcohol-ethylene oxide) copolymer in connection with the first embodiment is equally applicable to and incorporated by reference in the present embodiment. In accordance with the phrase xe2x80x9cconsisting essentially ofxe2x80x9d, the ink-receiving layer will not contain therein any pigments, fillers (of a particulate or non-particulate nature), supplemental binder compositions, or other materials in more than negligible/trace quantities (for example, those quantities that would incidentally be present as a result of the manufacturing processes being employed). In other words, the ink-receiving layer in the current embodiment will not include any pigments, fillers, or other materials therein aside from minute, trace amounts that would be considered inconsequential. Likewise, as a general proposition, the ink-receiving layer in this embodiment will not contain therein any composition(s) that would materially affect or alter any of the key characteristics listed above in connection with the use of a poly(vinyl alcohol-polyethylene oxide) copolymer. Such key characteristics include but are not restricted to gloss-control (with high gloss levels and gloss-uniformity being of primary interest under this category), excellent light-fastness, rapid drying time, the ability to control/prevent ink-coalescence problems, and the generation of clear, durable, smear-fast, and distinct printed images. In the current embodiment (which, while preferred and novel, shall not be considered the only embodiment in this case), it is therefore desired that the ink-receiving layer of interest be fabricated so that it is xe2x80x9ccopolymer onlyxe2x80x9d from a material-content standpoint relative to the poly(vinyl alcohol-ethylene oxide) copolymer discussed herein (e.g. optimally about 100% by weight of at least one poly(vinyl alcohol-ethylene oxide) copolymer. This numerical value shall again involve the total quantity of poly(vinyl alcohol-ethylene oxide) copolymer being used whether only a single copolymer is employed or multiple poly(vinyl alcohol-ethylene oxide) copolymers are used in combination. However, in accordance with the definitions listed above, it is possible that additional materials (namely, preservatives, surfactants, and others) may be added to the ink-receiving layer as needed and desired provided that they again fit within the foregoing definitions with particular reference to the phrase xe2x80x9cconsisting essentially ofxe2x80x9d and the legal meaning of this term. It should also be noted that the ink-receiving layer(s) xe2x80x9cconsisting essentially ofxe2x80x9d at least one poly(vinyl alcohol-ethylene oxide) polymer are preferably the uppermost layer(s) in the print media product. However, they may again be placed in other locations on or within the print media product as long as they are able to receive thereon or therein at least some of the ink being delivered by the chosen printing system.
In a still further alternative embodiment, at least one additional (optional) material layer (e.g. one or more of such layers) can be positioned between said substrate and the ink-receiving layer(s) in the claimed print media products if needed and desired as determined by routine preliminary pilot testing. The use of this additional material layer is applicable to all of the embodiments discussed above and all others encompassed within the claimed subject matter. The content of this additional material layer can vary without limitation regarding the types and amounts of compositions which can be used therein. For example, the additional material layer can be comprised of at least one binder, at least one pigment, or mixtures thereof. Likewise, at least one poly(vinyl alcohol-ethylene oxide) copolymer can be used in the additional material layer alone or combined with various pigments, binders, combinations of pigments and binders, and other compositions (e.g. fillers, surfactants, etc.) without limitation. Again, one or more of the additional material layers can be used in this embodiment, with such layers also being appropriately characterized as xe2x80x9cmedialxe2x80x9d or xe2x80x9cintermediatexe2x80x9d layers since, in the completed product, they will be located between the substrate and ink-receiving layer(s). In this regard, the additional material layer (if only one is used) will be secured by xe2x80x9cdirect attachmentxe2x80x9d (preferred but not required) to the substrate, with the ink-receiving layer (if only one is used) being secured by xe2x80x9cdirect attachmentxe2x80x9d (preferred but not required) to the additional material layer. However, it should generally be stated that the additional material layer is operatively attached to the substrate, with operative attachment as a basic term being defined above.
As a point of general information, the layers of materials associated with all of the embodiments expressed herein may be placed on only one side (preferred) of the coated or uncoated substrate or on both sides without limitation. If a coated substrate is employed, it is again particularly desirable to place the material layers on the coated side(s) as previously stated. Likewise, a number of different manufacturing techniques may be implemented in connection with the various embodiments of this invention without restriction as outlined further below. However, from a general standpoint, the claimed methods of interest regarding the above-listed embodiments will encompass the following basic steps (with the previously-described information involving construction materials, size parameters, and the like being incorporated by reference in the current discussion): (1) providing a substrate; and (2) applying at least one ink-receiving layer in position over and above the substrate. As previously discussed, the ink-receiving layer can involve a number of different formulations without limitation provided that it includes at least one poly(vinyl alcohol-ethylene oxide) copolymer therein. All of the information listed above regarding the ink-receiving layer formulations and the various embodiments associated therewith (including the materials, material quantities, and the like as previously discussed) are incorporated in this section by reference. In a first embodiment, the ink-receiving layer employed in the above-cited method includes at least one additional ingredient therein. For example, the poly(vinyl alcohol-ethylene oxide) copolymer(s) of interest may be combined with (A) at least one pigment; (B) at least one supplemental binder composition; or (C) a combination both materials (at least one pigment+at least one supplemental binder composition). While the present invention shall not be restricted to any particular numerical quantity values, it is preferred in the current xe2x80x9cmixedxe2x80x9d embodiment [e.g. where the poly(vinyl alcohol-ethylene oxide) copolymer is combined with one or more additional ingredients] that the ink-receiving layer be formulated to contain not less than about 70% by weight poly(vinyl alcohol-ethylene oxide) copolymer. Again, this value will involve the total amount of poly(vinyl alcohol-ethylene oxide) copolymer being used whether single or multiple poly(vinyl alcohol-ethylene oxide) copolymers are employed.
In another embodiment associated with the above-listed method, the ink-receiving layer will involve a structure xe2x80x9cconsisting essentially ofxe2x80x9d at least one poly(vinyl alcohol-ethylene oxide) copolymer with the term xe2x80x9cconsisting essentially ofxe2x80x9d being defined above and incorporated by reference in this section. In accordance with the phrase xe2x80x9cconsisting essentially ofxe2x80x9d, the ink-receiving layer will not contain therein any pigments, fillers (of a particulate or non-particulate nature), supplemental binder compositions, or other materials in more than negligible/trace quantities (for example, those quantities that would incidentally be present as a result of the manufacturing processes being employed). In other words, the ink-receiving layer in the current embodiment will not include any pigments, fillers, or other materials therein aside from minute, trace amounts that would be considered inconsequential. Likewise, as a general proposition, the ink-receiving layer in this embodiment will not contain therein any composition(s) that would materially affect or alter any of the key characteristics listed above in connection with the use of a poly(vinyl alcohol-polyethylene oxide) copolymer. Such key characteristics include but are not restricted to gloss-control (with high gloss levels and gloss-uniformity being of primary interest under this category), excellent light-fastness, rapid drying time, the ability to control/prevent ink-coalescence problems, and the generation of clear, durable, smear-fast, and distinct printed images. In the current method (which, while preferred and novel, shall not be considered the only embodiment in this case), it is therefore desired that the ink-receiving layer of interest be fabricated so that it is xe2x80x9ccopolymer onlyxe2x80x9d from a material-content standpoint relative to the poly(vinyl alcohol-ethylene oxide) copolymer discussed herein (e.g. optimally about 100% by weight of at least one poly(vinyl alcohol-ethylene oxide) copolymer. This numerical value shall again involve the total quantity of poly(vinyl alcohol-ethylene oxide) copolymer being used whether only a single copolymer is employed or multiple poly(vinyl alcohol-ethylene oxide) copolymers are used in combination. However, in accordance with the definitions listed above, it is possible that additional materials (namely, preservatives, surfactants, and others) may be added to the ink-receiving layer in this embodiment as needed and desired provided that they again fit within the foregoing definitions with particular reference to the phrase xe2x80x9cconsisting essentially ofxe2x80x9d and the legal meaning of this term.
The completed print media products described herein are designed to receive and retain a printed image thereon in a highly effective manner. The novel features discussed above individually and collectively constitute a significant advance in the art of image generation and print media technology. In particular, the unique structures, components, and methods of the invention with particular reference to the fabrication of an ink-receiving layer which includes therein at least one poly(vinyl alcohol-ethylene oxide) copolymer offer many important benefits compared with prior systems and products including but not limited to: (1) a high level of light-fastness, with the term xe2x80x9clight-fastnessxe2x80x9d being generally defined herein to involve the capacity of a print media product to retain images thereon in a stable fashion without substantial fading, blurring, distortion, and the like over time in the presence of natural or made-made light; (2) rapid drying times in order to avoid smudging and image deterioration immediately after printing is completed due to contact with physical objects and the like; (3) the fast and complete absorption of ink materials in a manner which avoids image distortion caused by color bleed (e.g. the undesired migration of multi-colored ink components into each other) and related difficulties; (4) a highly water-fast character (with the term xe2x80x9cwater-fastxe2x80x9d being generally defined to involve the ability of a print media product to produce a stable image with little or no fading, run-off, distortion, and the like when the image is placed in contact with moisture); (5) the generation of xe2x80x9ccrispxe2x80x9d images with a distinct and defined character; (6) the ability to produce printed products which are substantially xe2x80x9csmear-fastxe2x80x9d, with this term being generally defined to involve the production of images that will not exhibit smearing, blurring, and the like when rubbed or otherwise physically engaged with a variety of objects ranging from the components of the printing apparatus being employed to the print operator""s hands, fingers, and the like; (7) the control of an undesired condition known as xe2x80x9cink-coalescencexe2x80x9d which is again defined herein to involve a phenomenon wherein wet ink droplets applied to an inkjet printing medium fail to spread sufficiently to eliminate the unprinted space between the droplets, thereby causing significant image deterioration problems; (8) the capacity to generate printed images with desired levels of gloss wherein the final product is characterized by uniform gloss levels throughout the entire image in order to achieve a professional and aesthetically-pleasing printed media sheet; (9) low material costs which enable the print media products of interest to be employed for mass market home and business use; (10) chemical compatibility with a wide variety of ink formulations which leads to greater overall versatility; (11) excellent levels of image stability and retention over long time periods; (12) minimal complexity from a production and material-content standpoint which leads to reduced fabrication costs and greater product reliability; and (13) a high level of gloss-control which is achievable in a rapid and effective manner during production through only minor adjustments in the manufacturing process. These and other benefits, objects, features, and advantages of the invention will become readily apparent from the following Brief Description of the Drawings and Detailed Description of Preferred Embodiments.